A tangent line L is drawn at the point (2, -4) on the parabola y2 = 8x . If the line L is also tangent to the circle x2 + y2 = a , then ‘a’ is equal to ____

The equation of tangent at (2, -4) to the parabola y2 = 8x is -4y = 4(x+2)⇒x+y+2=0If this line is a tangent to the circle x2 + y2 = a then a=21+1⇒a=2⇒a=2

Book Online Demo

Check Your IQ

Try Test

Courses

Dropper NEET Course Dropper JEE Course Class - 12 NEET Course Class - 12 JEE Course Class - 11 NEET Course Class - 11 JEE Course Class - 10 Foundation NEET Course Class - 10 Foundation JEE Course Class - 10 CBSE Course Class - 9 Foundation NEET Course Class - 9 Foundation JEE Course Class -9 CBSE Course Class - 8 CBSE Course Class - 7 CBSE Course Class - 6 CBSE Course

Offline Centres

A tangent line L is drawn at the point (2, -4) on the parabola y² = 8x . If the line L is also tangent to the circle x² + y² = a , then ‘a’ is equal to ____

see full answer

Talk to JEE/NEET 2025 Toppers - Learn What Actually Works!

Real Strategies. Real People. Real Success Stories - Just 1 call away

An Intiative by Sri Chaitanya

answer is 2.

(Unlock A.I Detailed Solution for FREE)

Ready to Test Your Skills?

Check your Performance Today with our Free Mock Test used by Toppers!

Take Free Test

Detailed Solution

The equation of tangent at (2, -4) to the parabola y² = 8x is -4y = 4(x+2) $\Rightarrow$ x+y+2=0
If this line is a tangent to the circle x² + y² = a then $\sqrt{a} = |\frac{2}{\sqrt{1 + 1}}| \Rightarrow \sqrt{a} = \sqrt{2} \Rightarrow a = 2$